one of my players just emailed me. in the campaign i'm running the party just landed on an island where they'll be stuck for several months until merchant ships come to get them off island. there's a trade city on the island but its in the boonies so transport ships are rare. anyway he wants to set up shop and offer his wizardly services for a fee to the people of the city. i don't have a problem with this but i've never really done it before. are there guidelines or rules in any of the core books for purchasing or leasing real estate? its easy enough to say 2sp for a night in a common room and 2 gp for a night in a good room, but i can't exactly say its gonna cost him $800/month plus 2 1/2 month security and no pets...

If this is a service valued by the king/governer/regend/lord/god of this island, they may put him up in a place for free, not to mention if he is a good ruler and realizes the PC's are stuck here, and instead of bitching they are offering services to the town.

Right on! Thanks! And btw, I think this scenario offers a lot of great opportunities for role playing. I've always wanted to do a settled phase in a game, with job income, neighborhood politics, etc. The hard part, it seems like, would be populating it with so many NPC's. But it seems like it could be really fun and give a rogue a chance to finally make really good use of innuendo, bluff, etc.

i already feel like i don't have enough details of this city. i only had one in planned for when they first landed last night and they didn't like the name and immediately went looking for another one. BAH!

You could always just say he breaks even, except for a few special circumstances that you could actually play as mini-adventures. Assuming you're into that.

Maybe he makes enough that the party can all live it up while on the island. You don't need to give a monetary value to it, just explain that for the month's they're there they don't have to pay for rent or food and maybe have them appear to get some respect from locals for whatever else is going to happen while they're on the island.

Alternately, he can build up the business (by re-investing all the profits) to the point that, when he leaves, it's a steady semi-permanent revenue stream for the party. Every six months they get their dividends of 600 gold pieces, hooray!(that'd probably require training a few apprentices, though)

2nd ed had a lot on costs of places and hirlings in the DMG. Nothing in 3rd ed as far as I know.

It all depends on what you, as a GM, want. If it is a small area, the fact is that the wizard is probably competing with the local Adept or Sorceror (or other hedge-mage), as there isn't a large market. Costs and his viablity in the market is dependent on not offending the locals and living with the existant magic-suppliers, or driving them out of business. Besides, a small locale cannot afford a wizard of much quality for long. At 25-50gp per spell level, that's a year's wage or more for many peasants in DnD terms.

If it is a large market, the above is less of a concern, but wizard shops may be regulated by the government or by guilds. So he would need to be careful toget the appropriate licensure and permits.

If the ruler is a paranoid WIzard, setting up a shop may be more of a death-wish, anyways, as the ruler would probably send troops and enforcers to keep the shop closed. If it were legal. And if it weren't, even if the ruler can't close the shop directly, he probably can exile or kill any patrons.

Anyways, costs:reasonable costs would be 2-10gp per day, for a small slot in a Market. Rent would run 50-250gp per month, depending on city size, location, and size of shop. It is entirely possible that in addition to rent in a market, some percentage of sales (2-5%) would be trimmed off the top for the market. For a traditional shop, licenses and permits could be a flat fee, of pretty much whatever value you like, or some percentage of the profits, from 5-20%.

Plus, there is always the possiblity of Mafia/Yakuza/mob connections, protection money, bribes for the local constablary, etc.

This exact thing is actually covered in the Sharn: City of Towers thing. It has renting costs, purchasing costs, etc etc. Same for living space. Also has a metric ton of other worthwhile stuff, even if you aren't running Eberron.

I have to run to class like 5 minutes ago or I'd quick look for you. But, either way, pick it up, it's quite worthwhile. Especially if you'll need to reference this and other minute details like it often, now or in the future.